Medical research

How signalling proteins affect wound healing

What do a scraped knee, a paper cut, or any form of surgery have in common? The short answer is a wound in need of healing—but the long answer lies in a series of biological activities that allow tissues to repair themselves.

Medical research

Solving a biological puzzle: How stress causes gray hair

When Marie Antoinette was captured during the French Revolution, her hair reportedly turned white overnight. In more recent history, John McCain experienced severe injuries as a prisoner of war during the Vietnam War—and ...

Medical research

Serotonin is a master regulator of neuroregeneration

Neuroregeneration entails not only neurogenesis, but also regrowth of lost connections and birth of non-neuronal cells. While adult neurogenesis in humans is only known to occur definitively in a few precisely circumscribed ...

Medical research

High-protein diets boost artery-clogging plaque, mouse study shows

High-protein diets may help people lose weight and build muscle, but a new study in mice suggests they have a down side: They lead to more plaque in the arteries. Further, the new research shows that high-protein diets spur ...

Oncology & Cancer

Preventing metastasis by stopping cancer cells from making fat

Olivier Feron, a researcher at the University of Louvain (UCLouvain) Institute of Experimental and Clinical Research, seeks to understand how metastases form from a tumor. He previously demonstrated that the most aggressive ...

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Cell (biology)

The cell is the structural and functional unit of all known living organisms. It is the smallest unit of an organism that is classified as living, and is often called the building block of life. Some organisms, such as most bacteria, are unicellular (consist of a single cell). Other organisms, such as humans, are multicellular. (Humans have an estimated 100 trillion or 1014 cells; a typical cell size is 10 µm; a typical cell mass is 1 nanogram.) The largest known cell is an unfertilized ostrich egg cell.

In 1835 before the final cell theory was developed, a Czech Jan Evangelista Purkyně observed small "granules" while looking at the plant tissue through a microscope. The cell theory, first developed in 1839 by Matthias Jakob Schleiden and Theodor Schwann, states that all organisms are composed of one or more cells. All cells come from preexisting cells. Vital functions of an organism occur within cells, and all cells contain the hereditary information necessary for regulating cell functions and for transmitting information to the next generation of cells.

The word cell comes from the Latin cellula, meaning, a small room. The descriptive name for the smallest living biological structure was chosen by Robert Hooke in a book he published in 1665 when he compared the cork cells he saw through his microscope to the small rooms monks lived in.

This text uses material from Wikipedia, licensed under CC BY-SA